ROME — Silvio Berlusconi on Tuesday promised to resign after a key vote indicated that the Italo media mogul and prime minister no longer has a majority in parliament.

The move is seen as the final act in the TV tycoon’s 17-year career as the leading man in Italian politics.

President Giorgio Napolitano, who met Berlusconi after the vote, issued a statement saying Berlusconi had assured him he will resign after crucial economic reforms are passed in a Senate vote planned for next week.

Berlusconi, who has been vacillating as Italy’s economic crisis deepens, on Tuesday mustered 308 votes in a routine budget bill, seven votes shy of the majority he needed in the 630-member Lower House of Parliament to prove that he is still in command.

Technically, Berlusconi won the vote. That’s because 321 deputies, most of them from the center-left opposition, abstained from voting to make it clear that Berlusconi now lacks support in his own camp.

Earlier in the day, a key Berlusconi coalition ally, Umberto Bossi, head of the Northern League, urged the 75-year-old TV tycoon to step down.

After the vote, opposition leader Pier Luigi Bersani called for Berlusconi to immediately hand in his resignation to Napolitano.

It was a bad day for Berlusconi, whose Mediaset TV group posted a 31% drop in nine-month operating profit to €368.2 million ($507.8 million), and shares closed down 2.94%.

The end of the media mogul’s political cycle may also take a longterm toll on Mediaset, which has long leveraged its political clout.

There are now several possible scenarios of an Italian political crisis which could lead to a caretaker government through 2013 or early elections to be held in January at the earliest.